The necklaces are approximately 20” long. The necklace has a proprietary blend (including titanium and germanium) of natural elements embedded in the necklace. These are two elements on the periodic table with unique micro vibrational frequencies. When near the skin they set up a tuning fork linking frequency within the water system in the whole body. The effect is amazing and can be viewed under a microscope as seen where the blood cells can be seen as more healthy and flowing separately. Medically proven with bio-meridian machine, electron microscope viewing blood flow and thermography. Works within the body to neutralize the harmful effects of EMF waves from cell phones computers and power lines by reducing red blood cell clumping known as Rouleaux effect. This enables cells to travel single file through capillaries that require only one cell at a time. The clasp is magnetic and adds to the effect. It can be worn in the water. It is more effective the more its worn. The biggest benefit of the BioField Necklace is its ability to increase strength and balance – a very helpful aid for older people who lose their balance. Also available - Biofield Vertigo Relief - Bracelet.